煤巷顶板分布式光纤监测的可行性试验研究  

Feasibility study on distributed optical fiber monitoring of coal roadway roof

作　　者：杜传伟 胡涛 李业宏 王嘉钰 DU Chuanwei;HU Tao;LI Yehong;WANG Jiayu(College of Civil Engineering,Qilu Institute of Technology,Jinan 250200,China;Shandong Provincial Coal Technology Service Co.,Ltd.,Jinan 250032,China)

机构地区：[1]齐鲁理工学院土木工程学院,山东济南250200 [2]山东省煤炭技术服务有限责任公司,山东济南250032

出　　处：《矿业安全与环保》2022年第5期81-88,共8页Mining Safety & Environmental Protection

基　　金：山东省自然科学基金项目(ZR2019MEE009);教育部产学合作协同育人项目(202102351007);山东省高校创新训练项目(S202113998090)。

摘　　要：在传统顶板点式监测的基础上,应用BOTDR对采煤工作面回采巷道煤巷顶板沉降位移进行分布式监测。首先通过对BOTDR监测原理和煤巷顶板变形状态的理论分析,提出应用锚杆(索)在煤巷顶板进行光纤定点布设,并根据BOTDR测量的相邻定点间光纤轴向应变和变形量,推导出光纤应变量化煤巷顶板沉降位移的数学表达式;然后进行煤巷顶板沉降的光纤定点拉伸和区段拉伸室内模拟试验,试验中光纤应变表征的位移与光纤拉伸距离的误差分别为0.690%和1.545%,拉伸距离和应变表征光纤位移基本一致;最后进行了采煤工作面回采过程中进风巷煤巷顶板的BOTDR现场监测试验,试验期间,光纤应变表征出最大沉降位移平均值为64.09 mm和135.63 mm的2个顶板沉降区域。与井下十字观测法测量值相比,顶板沉降变形范围的最大误差为5.60%,顶板沉降位移的最大误差为4.96%,顶板垂直位移的绝对误差值小于4 mm,证明了BOTDR定量表征顶板的沉降变形范围和沉降位移的可行性。Based on the traditional roof“point”mode monitoring,BOTDR was applied to the distributed monitoring of the roof settlement displacement of the coal roadway along the trough in coal face.Firstly,through the theoretical analysis of BOTDR monitoring principle and the deformation state of coal roadway roof,it was proposed to use rockbolt(anchor cable)to carry out optical fiber fixed-point layout in the roof of coal roadway.According to the optical fiber axial strain and deformation measured by BOTDR between adjacent fixed points,the mathematical expression of optical fiber strain quantifying the roof settlement displacement in coal roadway was derived.Then,the indoor tests of fiber-optic fixed-point stretching and fiber-optic section stretching were carried out to simulate the roof settlement.In the tests,the errors between the displacement represented by the fiber-optic strain and the fiber-optic stretching distance were 0.690%and 1.545%respectively,the stretching distance and the displacement represented by the fiber-optic strain are basically the same.Finally,BOTDR field monitoring test of coal roadway roof in air inlet roadway during the mining process of coal face was carried out.In the field test,there showed two roof settlement areas characterized by the optical fiber strain.The maximum settlement displacement of the tow areas were 64.09 mm and 135.63 mm respectively.Compared with the underground cross observation method,the maximum error of the roof deformation range is 5.60%,the maximum error of roof settlement displacement is 4.96%,the absolute error of vertical roof displacement is less than 4 mm,which showed the feasibility of BOTDR in quantitatively characterizing the roof settlement range and displacement.

关 键 词：煤巷顶板 沉降位移 分布式光纤监测 布里渊时域反射技术 

分 类 号：TD76[矿业工程—矿井通风与安全] TD326